This invention relates to ultrasonic diagnostic imaging systems and, in particular, to ultrasonic diagnostic imaging systems which automatically assist in the assessment of cardiac performance and deficiencies.
Many ultrasonic diagnostic procedures in which bodily functions and structures are quantified rely upon clear delineation and definition of the body structures and organs which are being measured. When the quantification or measurement procedure uses static images or a small set of measurements, the delineation of the bodily structure being measured can be done manually. An example of such a procedure is the obstetrical measurements of a developing fetus. Static images of the developing fetus can be acquired during periods when fetal activity is low. Once an image is acquired, only a few circumference or length measurements are usually required to compute development characteristics such as gestational age and anticipated delivery date. These measurements can readily be made manually on the fetal images. Other diagnostic procedures, particularly those involving measurements of the heart and its functioning, present a further set of difficulties. The heart is always beating and hence is always in motion. As it moves, the contours of the heart constantly move and change as the organ contracts and expands. To fully assess many characteristics of cardiac function it is necessary to evaluate many and at times all of the images acquired during the heart cycle (one heartbeat), which can amount to thirty to one hundred and fifty or more images. The structure of interest such as the endocardium, epicardium or valves must then be delineated in each of these images, a painstaking, time-consuming task. Since these structures are constantly in motion, they appear slightly different in each image acquired during the cardiac cycle, and can also vary significantly from one patient to another. While applications such as obstetrical procedures would benefit from a processor which automatically delineates specific anatomy in an ultrasonic image, cardiac diagnosis would benefit even more so.
Once anatomy can automatically be delineated in cardiac images, it then becomes desirable how to make the best diagnostic use of the delineated image information. It is desirable, for instance, to convey a sense of regional wall motion but in a format which enables the user to specifically diagnose particular locations of the heart wall and to be able to do so over the full cardiac cycle. Furthermore, it is desirable to give the user a visual, automated assessment of regional cardiac performance, enabling the user to quickly pinpoint and thereafter examine potentially deficient regions of the heart.
In accordance with the principles of the present invention, ultrasonic cardiac image information is acquired and segmented by automatic border detection. The segmented ultrasonic information is used to display regional wall motion over time. The segmented information may be presented in a color-coded representation, or entered automatically as qualitative or quantitative measures on a scorecard of cardiac performance. The inventive technique is applicable to both two dimensional and three dimensional ultrasonic image information.